Strong contenders

Two recent University of Arkansas releases show improvements over earlier varieties in two sets of different trials.

By Ryan McGeeney
University of Arkansas Division of Agriculture

Xuyan Sha

University of Arkansas rice breeder Xueyan Sha gives attendees of this summer’s Rice Expo research tour an update on rice breeding efforts at the Rice Research and Extension Station near Stuttgart—photo by Vicky Boyd

Diamond and Titan, conventional long- and medium-grain rice varieties developed by the University of Arkansas, should offer strong yields and other advantages to growers, according to preliminary data from this year’s rice performance trials.

Jarrod Hardke, Extension rice agronomist for the Division of Agriculture, says each performed well in a difficult growing year.

“They both seem to represent further yield improvement over previous releases,” Hardke says.

Diamond showed appreciable yield increases over currently grown long-grain varieties, including Roy J, LaKast and CL151, he says. Titan showed particular advantages over other medium-grain varieties such as Jupiter and CL272.

Two trial programs

The preliminary data were drawn from two annual small-plot rice trial programs — the Arkansas Rice Performance Trials, or ARPT, in which 75 commercial and experimental rice cultivars were planted and closely monitored by Division of Agriculture researchers at five research locations with varying soil and climate. Of the 75 entries in ARPT, only the lead 23 commercial and experimental entries have been summarized to date.

Rice varieties also go through the Producer Rice Evaluation Program, known as PREP. This year, 20 cultivars were planted by researchers in nine counties.

In this program, the cultivars grow in fields managed by a cooperating farmer in the same manner as the rest of the field surrounding the plot.
According to the preliminary ARPT data, the mean yield for Diamond long-grain was 197 bushels per acre, and 201 bushels per acre for Titan medium-grain. The mean for all cultivars grown at the four research station locations was 186 bushels per acre.

In the PREP trials, Diamond produced a mean yield of 207 bushels per acre, and Titan’s mean yield was 205 bushels per acre. The mean for all cultivars grown at the nine selected private farms was 198 bushels per acre.

“The PREP trials are all strictly on-farm with a more or less ‘plant it and leave it’ approach,” Hardke says. “I don’t dictate anything — we simply plant it, and the growers manage the field as they would manage it anyway.

“We can come back and take notes — we learn as much as we can from it — but the main thing is to come back at harvest and see how all those cultivars perform under those management conditions, in a particular geography.”

Hardke says XL753, a RiceTec hybrid, continued to set the bar for yield across the board as it has in recent years, yielding 239 bushels per acre in the ARPT and 242 bushels per acre in PREP. Other RiceTec hybrids also performed well.

Varying climate, soils a challenge

Hardke says the variation in soils and growing conditions throughout Arkansas makes developing reliable recommendations for rice growers but one he readily accepts.

“Probably what makes Arkansas so unique as a rice-producing area is that we have a very broad range of production conditions,” Hardke says. “We have production areas similar to the Bootheel of Missouri, the Mississippi Delta, northeast Louisiana, in addition to many other production areas that are completely unique to us. So when we try to move to these on-farm trials and make sure we’re capturing all these different areas of the state and different production practices — there’s a lot of variability to try to capture, from different environments and production practices.”

Despite the positive data, Hardke cautions interested growers to exercise prudence in adopting any new cultivar.

The Division of Agriculture will publish its final findings from the trials in December.